The present invention relates to a plug locking device.
Electric vehicles, which reduce carbon dioxide emissions, have become popular in recent years. Such an electric vehicle uses a battery to power a motor. Whenever the state of charge of the vehicle battery becomes low, the battery is charged, for example, with a household outlet or at a charging station. Japanese Laid-Open patent Publication No. 9-161898 describes a power feeding plug connected to a distal end of a power cable. The power feeding plug is connected to an inlet of a vehicle to charge the vehicle battery.
The time required to charge the battery of an electric vehicle is still much longer than the time required to refuel a gasoline engine vehicle. As a result, the vehicle may be left unattended over a long period of time with the power feeding plug connected to the inlet of the vehicle. In such a case, someone may wrongfully remove the power feeding plug and connect it to another vehicle to steal electricity or steal the power feeding plug.
FIG. 8 shows a referential example of a locking device 101, which locks a power feeding plug to an inlet 102 of a vehicle and prevents unauthorized removal of the power feeding plug. The locking device 101 is formed integrally with the inlet 102. The inlet 102 includes a plug port 103, which receives the power feeding plug, and a hooking hole 104, which is formed above the plug port 103. When the power feeding plug is connected to the inlet 102, the hooking hole 104 receives a hook of the power feeding plug. The hook is engaged with a projection in the hooking hole 104. A lock bar (not shown) of the locking device 101 blocks the hook in the hooking hole 104 to prevent the hook from being released from the hooking hole 104. This prevents unauthorized removal of the power feeding plug.
The inlet 102 is arranged in a side wall of the vehicle in the same manner as a fuel filler inlet of a gasoline vehicle. In the referential example shown in FIG. 8, bolts 106 fasten the locking device 101 to the vehicle. When the locking device 101 is coupled to the vehicle from the outer side by the bolts 106, the head of each bolt 106 is exposed toward the outer side of the vehicle. The locking device 101 prevents unauthorized removal of the power feeding plug from the plug port 103. However, when the bolts 106 are unfastened with a tool, the locking device 101 may be removed from the vehicle.
To solve this problem, the bolts 106 may fasten the locking device 101 to the vehicle from the inner side of the vehicle. However, the fastening of the bolts 106 from the inner side of the vehicle would be complicated.